Grate.



E. C. WILEY. GRATE.

APPLICATION FILED 0012.4, 1909.

1,01 5,527. Patented Jan. 23, 1912.

3 SHEETS-SHEET 1.

/T Lrm/VTM: l au.. @2%

coLUMBM PLANOGRAPH co.,wAsHlNa1'oN. D. c.

E. C. WILEY.

GRATE.

APPLICATION FILED 00T.41, 1909.

Patented L1m29), 1912.

3 SHEETS-SHEET 2.

INV NTOR Q, s.

l mMAllowy/I WITNESSES coLuMBlA PLANOURAPH Co.. WASHINGTON. D. c.

E. C. WILEY.

GRATE.

APPLICATION FILED 00124, 1909.

Patented Jan. 23, 1912i s SHEETS-SHEET s.

UNITED' sTATEs PATENT oEEroE.

EDGAR C. AVVILIEY, 0F LYNCHBURG, VIRGINIA.

GRATE.

f Application led October M1909. Serial No. 520,819.

To all 'whom 'it may concern:

Be it known that I, EDGAR CLARENCE WILEY,` a citizen of the United States, residing at Lynchburg, in the county of Campbell and State of Virginia, have invented certain new and useful Improvements in Grates, of which the following is a specification.

My present invention relates to grates in'- tended particularly for the burning of nely divided fuel, and is particularly adapted to that type of furnaces in which a portion of the air is caused to pass directly7 upward through the fire, while other air is caused to pass through passages formed in the grate bars and is then discharged in its highly heated condition alcovel the re, to effect the complete combustion of any unburned gases.

The invention resides in the particular form of the'bar and in the use therewith of a second type of bar adapted to `admit air direct from the ash pit to transverse ducts formed by the assembling of a series of bars.

By my particular construction I secure a bar of truss or girder form, giving a peculiarly even distribution of. draft throughout ,the entire area of the grate andcooled by the air passing through the above mentioned ducts at points where the bars are likely to be highly heated. p

The invention will be described in detail in connection with the accompanying drawings, wherein, Y

Figure 1 is a transverse vertical sectional elevation of the boiler setting and gratefthe latter being shown in section throughout, the end portions being taken upon the line af-a of Fig. 2, while the central sectionv is taken upon the line b-- of said figure; Fig. 2 is a ylongitudinal vertical section of'the same, the plane of section being taken on the line o-o of Fig. 1; Fig. 3 is a perspective view of a special bar used to admit air to the ducts in the bars as above mentioned; Fig. 4 is a perspective' view of la 'regular grate bar, and Fig. 5 is a plan view on a slightly enlarged scale of a portion of yKhe grate assembled as illustrated in Figs. 1 and 2.

Like numerals refer throughout the drawings.

Referring toV the drawings, 1 represents the boiler shell and 2 the brickwork of the setting.

3 is the assembled grate and 4 one of the to like parts ducts formed therein, conveying air from y the ash pit 5 by the passages 6 to a point `pit 5 to the ducts 4, and a seriesof dampers 8 mounted upon a damper shaft 9 is yfurnished to vary the opening leading to the ducts, 4. The grate bars are supported at the masonry of the sett-ing.

Having described the manner of assembling and supporting the bars in the furnace, it now remains to describethe particular forms of the regular and of the special bars. By reference to Fig. 4 the form of the regular bar can be best understood. The bar is vcast in one piece and ,comprises two chords 11 and 12, practically parallel with each other throughout their length. The upper chord 11 is practically straight and is of trapezoidal cross section `witha reinforcing rib 13 on its under side. Inthis way this upper member 11 is wider at the top than at the bottom, so that ashes falling between the bars when assembled in the grate will be given ready clearance. The lower member 12 is approximately rectangular inform but slightly rounded on its upper face to prevent the collection of ashes falling between the upper members. The chord 12 is practically straight throughout its length but curves upward at its ends as at 14, and joins the upper chord 11 at 15. The upper chord 11 projects beyond this point of juncture 15, and forms a foot or lug 16 at eachend of the bar, intended to support the grate bar upon the bearing bars when in position in the furnace. Intermediate the point of juncture 15 and preferably at regular intervals is a series of enlargements 17 connecting the upper and lower chords with which they are cast integrally. These enlargements have approximately the form of cylinders with their axes transverse to the bar, and are formed with openings 18, which, when a series of the bars is assembled, register and form the continuous ducts 4 already mentioned. These enlargements measured in the direction transverse to the bars areslightly wider than the widest part of the chords 11, so that when a Series of bars is assembled, with these enlargements in contact, an interval exists between the upper chords of adjacent bars. These intervals or slots are interrupted only at the enlargements 17, so that when a series of bars is assembled there is labove the fire. The special bar 7 is illus- ,trated as furnishing the inlets from the ashA their ends uponbearing bars 10 carried byy between .each pair of bars an interrupted slot like air opening. To obviate as much as possible the obstructive effect of these interruptions in the air openings at the enlargements 17, and to prevent over heating, transverse grooves 19 are formed in the upper faces of the members 11, adjacent these enlargements. In this way, air coming up through the air openings is caused to flow over the top surface of the bar at these points.

To secure accurate register of the openings 18 and form continuous and approximately air tight ducts 4, the enlargements 17 are formed with annular projections or bosses 20 and corresponding recesses 21, upon opposite sides so that the projections f on one bar shall engage the recesses upon its neighbor. (See Fig. 1.)

As will be seen by reference to Fig. 3 the special bar is essentially identical with the regular bar just described. It haslan jf upper chord 22 of the same cross section as f' as will be described in detail.

the lugs 16.

. assembled.

The enlargements 27 are provided with openings 28 transverse the bar, but these openings 28 are cut away at their lower side as at 29 :so that the ducts 4 described as formed by the assembling of a plurality of bars may be connected through 29 with the ash pit 5. Aside from thel cutting away of the lower portion the enlargements 27 differ from the enlargements 17 ofthe regular bars only in having depending lips or projections 30 of suitable thickness. This is for the purpose of giving increased strength at these points, required because of the cutting away of the chord '23. Grooves 31 identical `in form and function with the grooves 19 are formed in the upper chords adjacent the enlargements 27, and annular bosses '32 and recesses 33 similar to the bosses and recesses 21 and 22 are provided.

In the practical use of my grate bars a plurality of regular bars is assembled in the furnace with the lugs 16 resting upon the bearing bars 10 and the bosses '2O of the bars engaging the recesses 21 Vof adjacent bars.

j The ducts 4 thus formed are caused by the design of the boiler setting to connect directly with the passages 6. Together withV these bars is .assembled van appropriate number of special bars preferably grouped together at one place so vas to form a single inlet forthe air to the ducts 4, thoughif desired for any reason, these bars may be distributed throughout the grate surface. Obviously the bosses 27 and recesses 28 of the special bar engage the recesses 2land bosses 20 of the regular bars.. The shaft 9 is properly located to bring the damper 8 to its correct position. The damper 8 is moved away fromV the openings 29 at the lower side of the special bar by a partial rotary movement of the shaft 9. As clearly shown in Fig. 5 the assembled bars form a grate conf In the manner above set forth I secure a grate bar simple in form and adapted to withstand any load that can ordinarily be brought upon it. The bars when assembled are interlocked so as to assist in maintaining each other in position. The flow of air through the grate to the fire is in no manner obstructed and yet I am enabled to use the heated condition of the grate to furnish highly heated air to the combustion chamber thus securing more perfect combustion than can otherwise be had. An incidental advantage is that the air drawn from the ash pit tends to vcool the grate bar, and that this cooling occurs at the point where strength in the bar is-required.

yI am aware that the system of passing air through grate bars to besubsequently liberated in the combustion chamber is well known, but in all such bars where the air has been taken from the ash pit the bars are' of a most complicated and unsatisfactory form. By my construction, however, made possible bythe use of the special bar, I seof the length of the bar and of the general design of the furnace. j Under certain conditions one might be sufficient', but in large furnaces having intensely hot fires a larger ico iis

number than the four illustrated may be found desirable.

Having thus described my invention, what I claim is Y 1.9A grate bar, comprising in combination, an upper chord; a lower chord; and a connection between said chords provided with'a transverse duct. Y Y

2. A grate bar comprising an upper chord; a lower chord; and connections between said chords provided with transverse air-ducts.v Y

'3. A grate' bar comprising an upper lao chord of trapezoidal cross section; a lower chord of narrower cross section; and connections between said chords, provided with ducts transverse to said bars.

4c. A grate bar comprising an upper chord of trapezoidal cross section; a lower chord; and connections between said chords of greater transverse width than said chords and having transverse ducts.

5. A grate bar comprising an upper chord; a lower chord; and connections between said chords of greater transverse width than said chords and having transverse ducts.

6. A grate bar comprising an upper chord; a lower chord; connection between said chords of greater transverse width than said chords and having transverse ducts; and means comprising interengaging projections and recesses for securing accurate register and connection of said ducts, when a plurality of bars is assembled.

7. A grate bar comprising in combination an upper chord of trapezoidal cross section grooved on its upper face; a lower chord; and connections between said chords provided with ducts transverse to t-he bar.

8. A grate bar comprising in combination an upper chord, grooved on its upper face; a lower chord; and connections between said chords provided with ducts transverse to the bar.

9. A grate bar comprising in combination a straight upper chord; a lower chord curved and united therewith at its ends; and a series of members connecting the upper and lowerchords and having transverse apertures.

10. Agrate bar comprising in combination a straight upper chord; a lower chord curved and united therewith at its ends; and a series of members of greater transverse width than said chords connecting the chords and having transverse apertures.

11. In combination with a furnace having an ash pit, a combustion chamber and passages leading from the grate level into the combustion chamber, a grate comprising a plurality of bars each formed with an upper chord, a lower chord, and apertured members connecting said chords and forming transverse ducts in the grate in communication with said passages, the connecting members of one of said bars opening into the ash pit.

In testimony whereof I have signed my name to this speciication in the presence of two subscribing witnesses.

EDGAR o. WILEY.

Witnesses:

KATIE JENNINGS; GRACE H. MAHoon.

Copies of this patent may be obtained for ve cents each, by addressing the Commissioner of Patents, Washington, D. C." 

